1. Field of the Invention
This invention relates to a filter system for a power transmitting device and, more specifically, to such a filter system which allows installation and removal of the filter thereof without removing the lubricating oil in the oil sump of the power transmitting device while verifying the level of the lubricating oil in the sump.
2. Description of the Prior Art
With the advent of heavy duty trucks for on-highway and off-highway use, there has been a continued emphasis in providing positive pressure lubricating systems for power transmitting devices used in such vehicles. With the increase in positive pressure lubricating systems, there has also been an increase in the number of such systems which utilize filters to insure the satisfactory quality of the lubricating oil. While some of these filter devices are mounted externally of the power transmitting device housing, there are others which are installed internally.
Generally, U.S. Pat. Nos. 2,492,831; 2,498,828; 2,896,479 and 3,550,724 disclose internally installed filter systems which might be applicable for the power transmitting devices found on such trucks. However, in some of these systems, the filters cannot be inspected or removed for cleaning without removal of all of the lubricating oil stored within the power transmitting device. Additionally, the method of flow through the filters disclosed therein would result in the entrapment of undesired particles externally of the filter making it more likely that the particles to be withdrawn from the system might accidently be left in the lubricating system when the filter is removed.
In any case, there remains a need for providing a filter system for a power transmitting device which will allow easy access to the filter for its inspection and removal.